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ZR-1 Shenandoah

Shenandoah is American Indian for "Daughter of the Stars". The ZR-1 was the American Navy's first attempt to develop a huge airship of the rigid type along the lines of the German Zeppelin L-49, which was captured intact during the war in France. This German craft, built after some 140 airships had been employed in actual service, was considered to represent the best construction of the Zeppelin engineers and works and was regarded as a safe and reliable craft.

The design was based on a German rigid shot down over England. On this design as a basis the American engineers were proceeding with the idea of making improvements suggested by experience rather than radical innovations. The construction was hampered by reduced appropriation. The ZR-1 had a length of 645 feet and a diameter of 78 feet, both the German standard dimensions, and was to be equipped with six Liberty engines, each of 400 horsepower and in a separate car as against the original plan of five engines. These engines in service were to be reduced to 320 horsepower each with a promised increased economy and reliability of operation.

The ZR-1, whose gas bags were designed for either hydrogen or helium, was to have a gas capacity of 2,000,000 cubic feet or some 700,000 cubic feet less than the ZR-2, while her lift was planned to be about twenty-seven tons less than that airship and be about equivalent to the fiftysix ton pull of the British R-34 which made the transatlantic trip. The speed was also planned to exceed the 60 mile maximum of German airships.

Her performance didn't meet expectations, partially because she was designed to carry hydrogen and used the heavier, but safer, helium. The new airship used helium gas, which has about eight per cent less lifting power than flammable hydrogen heretofore used. On account of this the bag must have a larger capacity to raise the same amount of dead weight. Helium gas is also too scarce and valuable to be released to regulate the altitude of the craft. In the ordinary hydrogen balloon and airship when it is desired to go higher ballast is thrown out and when necessary to descend gas is let out. In the new helium aircraft, the necessity of valving or throwing out ballast is partly compensated for by cooling or heating the helium and thus causing it to contract or expand as desired.

Using the gasoline fuel during a long trip would ordinarily lighten the ship and cause it to rise. But loss of weight in fuel is compensated for hy collecting the water in the exhaust gases formed by the hydrogen in the gasoline combining with the oxygen of the air in the engines. For one hundred pounds of gasoline used there was about one hundred pounds of water produced and the weight approximately equalized.

USS Shenandoah, a 2,115,000 cubic foot rigid airship, was fabricated at the Naval Aircraft Factory, Philadelphia, Pennsylvania, and assembled at Naval Air Station Lakehurst, New Jersey, in Hangar one. Components were built in Philadelphia and shipped to Lakehurst. The duralumin for the girders of the ship's framework were delivered to the Philadelphia aircraft plant of the Navy where it was being fabricated into the lattice work frame members. The contract was let for the eighteen gas bags, while arrangements were being made to lay the keel in the new hangar which had been built at Lakehurst, NJ, and completed during the year to house both the ZR-1 and ZR-2. Here the frame members which had been cut and assembled for fitting at Philadelphia were to be transported and then reassembled and placed in the ship.

She first flew on 04 September 1923 and was placed in commission slightly over a month later. During the final four months of 1923 and the first weeks of 1924 Shenandoah made several flights around the eastern United States, giving the American people their first view of a U.S. owned rigid airship and providing valuable training to her as yet inexperienced crew. Following storm damage in mid-January 1924, she was repaired and overhauled, returning to service in May. In August 1924 the airship conducted the first of many moorings to a ship, the specially-converted oiler Patoka.

In October 1924 Shenandoah made a round-trip voyage to the West Coast, flying by way of Texas, and was briefly based at San Diego, California. She was laid up at Lakehurst upon her return in late October, thus freeing scarce and expensive helium for use in the new dirigible Los Angeles, and was not back in active service until June 1925. That summer she carried out tactical exercises with the Fleet, her only real employment with the Navy's "mainstream" operating forces.

Nearly two years to the day after her first flight, she crashed on 03 September 1925. During the first leg of a publicity flight to the Midwest, USS Shenandoah encountered violent weather over southern Ohio, broke up in flight and was a total loss. The control car and after section fell directly to earth, while the forward section with seven aboard free-ballooned. LCDR C.E. Rosendahl (who would become the C.O. of NAS Lakehurst) controlled its free-ballooning for one hour before safely landing twelve miles from the crash.Fourteen of her complement lost their lives in this tragedy, including the C.O., LCDR Zachary Lansdowne. Twenty-nine crew members survived.

ZR-1 Specifications

Powerplant: Six 300 hp Packard engines

Length: 680 feet

Diameter: 79 feet

Volume: 2.1 million cubic feet

Crew: 23

Max speed: 60 mph



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Page last modified: 07-07-2011 02:39:59 ZULU